Electric switch



QA. o. AUSTIN 1,740,640

ELECTRIC SWITCH Filed may 25,` 1925 e sheets-sheet 1 Dec. 24, 1929.

I N V EN TOR.

ATTORNEY DC- 24, 1929. A. o Aus-rm 1,740,640

ELECTRIC SWITCH s sheets-sheet 2 Filed May 25'. 1925 I N VEN TOR.

www x/M A TTORNEYA` Dec. 24, 1929.

A. Q. AUSTIN ELECTRIC swITcH Filed May 25, 1925 6 Sheets-Sheet 3 m. m m N I ATTORNEYS Dec. 24, 1929. A. o. AUSTIN ELECTRIC SWITCH Filed May 25. 1925 6 Shvsze's-SheerI 4 r. l5 i... e

NVENTOR. M t 1 BY m I.

A TTORNEYS Dec-. 24, 1929. A. o. AUSTIN 1,740,640

ELECTRIC SWITCH Filed May 25, 1925 6 Sheets-Sheet 5 INVENTOR.

BY f (Q @WQ m ATTORNEYJ' Dec. 24, 1929. A. o. AUSTIN ELECTRIC SWITCH Filed May 25, 1925 6 Sheets-Sheet 6 @Ma/1 [Nfl/5IN TOR.

ATTORNEYJ Patented Dec. 24, 1929 UNITED STATES PATENT OFFICE ARTHUR O. AUSTIN, OF BARBER-TON, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

THE OHIO BRASS JERSEY COMPANY, OF MANSFIELD, OHIO, A CORPORATION OF NEW ELECTRIC SWITCH Application led May 25,

purpose named which shall be of improved construction and operation and in which the switch blade may be more readily moved into and out of closed position than is possible in case of switches heretofore constructed.

The invention is exemplified in the combination and arrangement of parts shown in.

the accompanying drawingsl and described in the A following specification and. it is more particularly pointed out in the appended claims.

In the drawings- Fig. 1 is an end elevation of a switch embodying one form of the present invention, the switch blade being shown in section.

' Fig. 2 is a transverse section on line 2-2 of Fi-g. 1.

Figs. 3 and 4 are side and end views respectively with parts in section showing. a modified form of the invention.

Fig. 5 is a longitudinal section of a different form of the invention.

Fig. 6 is a section on line 6 6 of Fig. 5.

Figs. 7 and 8 are ,views similar to- Figs. 5 and 6 respectively showing a ldifferent modification of the invention.

Fig. 9 isan end elevation of. another form Aof the invention.

Fig 10 is a side elevation of the fl'm shown in Fig. 9.

Figs. 11 and 12 are end and side. elevations respectively of another modification.

Fig..13 is a view similar to Fig. 9 but showing the position taken bythe segments when the switch is open.

In heavy duty switches and especially in the case of switches which are exposed to weather vconditions or which are opened only occasionally, difficulty is frequently eXperienced in moving the blade relative to the fixed contacts. If the parts are corroded, this difficulty is increased and is especially noticeable where the switches are mounted in position where they are not easily accessible. The present invention overcomes these objections and at the same time provides efficient 1925. Serial No. 32,718.

electrical contact between the relatively movable parts.

In the form of the invent-ion shown in Figs. 1 and 2, the numeral 1() designates a base block from which fingers 11 extend.

The fingers 11 are spaced apart and arranged paratively heavy springs 16 are secured to the blocks 10 and engage the outer faces of the rollers tending to press them inwardly into engagement with the blade 12. Arcing horns. 17 may be provided to prevent arcing to the'ingers 11. It will be noted that the outer ends of the fingers 11 are curved outwardly as shown at 18 to provide ample pickup for the blade 12 as it is moved into engagement with the rollers 14.

In Fig. 1, the rollers are shown in full line position atthe point where the blade first engages them as the switch is closed. As shown in that figure, theblade is given a wed e shape so that as it enters between the ro ers, the rollers are forced outwardly against the force of the spring 16. This insures firm engagement to provide good elecy trical connection but at the same time perlnits easy movement of the blade since it travels on freely movable rollers which in turn roll upon the inner surfaces ofthe springs 16. The blade may be provided with notches 19 having the same radius of curvature as the rollers 14 so that when the blade reaches its innermost position shown in broken lines in Fig. 1, these springs will force the rollers into the not-ches, thus, insuring good electrical contact and holding the blade in Aits closed position. The friction between the rollers and spring 16 will prevent the blade and rollers from dropping downwardly, however, a relatively'I slight force on the blade tending to open it will overcome the ,spring tension pressing the rollers into the notches 19 so that the blade may bereadily opened and when the rollers are once removed from the notches, the taper On the blade will co-operate with the spring pressure to assist in opening the blade. The traveling engagement between the blade and rollers und-er the force ofv the spring 16 will assist in breaking any coating on the blade due to corrosion, sleet or other cause and thus, insure a good electrical contact between the roilers and blade.

IVhere the switch operates in a horizontal position or in any position in which the rollers do not gravitate to the extreme end of their travel as shown in Fig. 1, resilient means may be employed to move the rollers to their outermost positionwhen they are free from the blade. Such an arrangement is shown in Figs. 3 and 4 of the drawing. In those figures, arms 2O are connected to the base block 10 outside of the springs 21 and these arms are provided with flanges 22 having slots 23 the'rein for retaining the rollers 24. A resilient roller may be employed as shown in this figure. A head 25 is carried on a plunger 26 which slides in an opening 27 in the base block 10 and is forced outwardly by a spring 28. The head 25 bears against the rollers 24 and move them into their outermost position whenever they are free from the blade 12. Pick-up members 28 similar to the members 18 in Fig. 1 are formed on the arms 20.

In the form of the invention shown in Figs. 5 and 6, balls 30 constitute the rollers for the blade 31 and are set in retainers 32 which move between flanges 33 and aretween the blade and stationary contacts.

Invthe form of the invention shown in Figs. 7 and 8, the arrangement is similar to that of Figs. 5 and 6 except thatl runways 38 are provided with studs 39 extending through openings in the backing plate 36. Coil springs 40 surround the studs 39 and press the runways 38 inwardly.

vIn the form of the invention shown in Figs. 9 and 10, the blade 40 is arranged to make rolling contact with arcuate segments 41. These segments are fixed to shafts or pins 42 which oscillate about pivot studs 43. Flexible conductors 44 provide electrical connection with the segments 41. Secured to the shafts 42 beyond the end of the blade other. Leaf springs 48 are rigidly fixed to the control segments and tend to move the segments into open position shown in Fig. 13. If the segments are closed, the leaf springs 48 are wound upon the control segments and placed under 'stress tending to open the segments.

In the form of the invention shown in Figs. 11 and 12, raceways are carried by resilient arms 51 and auxiliary springs 52 bear upon the raceways to press them toward each other. The raceways 50 are provided with slots at their inner edges through which ball bearings 53 project to engage the blade 54. rIhe slots in the faces of the raceways are of less width than the diameter of the ball bearings 53 so that the bearings are retained in the raceways.

In disconnecting or high tension switches, particularly those which are used infrequently or which are placed in the open, it is quite common t-o have the switch held up owing to poor contact or to stick in opening or closing.

The sticking in opening or closing is likely to be occasioned by corrosion of the contacts, loss of the lubricant, or accumulation of dirt, which so increase the coefficient of friction that the switch is opened or closed with difficulty or a much stronger insulator is required to insure safe operation of the switch.

In the present invention, the switch is so made that the accumulation of dirt, corrosion or loss of lubricant, affects the opening or closing of the switch but little. In addition, the switch is such that a very high pressure is permissible between the operating parts without the necessity of causing the componentparts of the switch to engage or disengaQe. In the present invention, the very high pressure which is possible with the small operating force insures contact between the several members. The fact that the area of contact may be made quite small can be used to advantage to insure Contact where parts become corroded or coated with dirt or sleet. The low working temperature of a switch under severe conditions depends more upon the pressure than upon the area of contact. A conducting surface which makes contact at several different points can conduct a large current without a high loss as the total resistance is small. This is due to the fact that the path of the current increases quite rapidly as the current flows away from the point of Contact. On switch parts having large areas of contact, the current is frequently carried at a few points and not over the whole surface, as the air or lubricating field may only be broken down at a few points unless excessive pressure is used.

This invention makes use of the high pressure in establishing contact, does away with the necessity of lubricant, and makes it possible to construct a switch which can be readily operated at all times.

The general principle of the roller contact in connection with the blade may be accomplished in one of several ways, such as with a number of rollers used in a single or multiple by a series of balls operating in slots or cages, or by segments or rollers to which conducting members are attached. In the case of the solid or flexible rollers or balls used for making contact, it is not necessary to provide pig tails or conducting members.

In very heavy current switches where the parts maybe quite rigid and of a high degree of accuracy, the flexibility may be taken up in the rollers or on the blades making contact. While the operation of the switch blade will tend to leave the various rolling cont-act members in proper position for the closing of the switch, it may be necessary to turn the mechanism so that gravity will seat the members properly or to use springs to see that they are in proper position for the closing of the switch. While the various drawings show only a single blade, it is seen that the construction is suitable for multiple blades as it is common practice.

I claim- 1. Anl electric switch having relatively movable switch members and roller contact means on one of said members for making rolling contact with the other of said members, said members being arranged to bear on substantially diametrical opposite sides of said roller contact means to provide electrical connection said roller contact means having its axis of rotation freely movable relative to the member on which it is mountedin a girection parallel to the surface ofsaid mem- 2. An electric switch having relatively movable switch members and a roller contact element for making electrical connection be? tween said members, said rollerrcontact element being free to move bodily relative to both of said switch members and having rolling contact with both of said switch members.

3. An electric switch having relatively movable switch members, one of said members having a resiliently held roller contact element for making electrical connection with the other of said members, said roller contact element being free to move bodily relative to both of said switch members and having rolling contact with both of said switch members.

4. An electric switch having relatively movable switch members, rollers mounted on one of said members, andsprings for pressing said rollers-toward each other to make electrical engagement with the other of said members, said rollers being free to move bodily relative to `-both of said switch members and having rolling Contact with both of said switch members. Y

.5. An electric switch comprising relatively movable switch members havingsurfaces disposed in registration when said switch is closed, and a roller interposed between said surfaces and having rolling contact with both of said surfaces when said members are moved relative to each other.

6. A switch comprising a pair of relatively movable members and a roller having rolling contact with both of said members during relative movement ofsaid members, one of .said members having a recess therein to en gage said roller when said sw1tch is 1n closed position.

7. A switch comprising spaced fixed contact members, rollers connected with said members but having their axes of rotation freely movable relative to said members in the direction of the contact surfaces of said members, springs for pressing said rollers inwardly, and a blade movable into and out of position between said rollers.

8. A. switch comprising spaced fixed contact members, rollers associated with said members .and movable relative thereto, springs having flanges engaging said rollers along which said rollers are arranged to travel, vand a `blade movable into and out of position between said rollers, said blade hav ing a recess therein for cooperating with one of said rollers to retain said blade in closed position.

9. A switch comprising a base block having a plurality of lingers arranged in sets projecting therefrom, rollers loosely carried by said fingers and disposed in registration with each other, the axes of rotation of said rollers being movable in the direction of the length of said lingers, springs bearing against the outer faces of said rollers, said fingers having outwardly curved portions, and a blade movable into and out of position between said rollers, said blade having elongated grooves on opposite faces thereof for engaging said rollers to retain said blade in closed position.

' 10. In combination a pair of relatively movable switch elements, a roller interposed between said elements and having rolling contact with both of said elements throughout the entire range of relative movement of Ysaid elements, said roller being arranged to limit the movement of said elements toward veach other and to provide electrical connecof switch elements, one of which is movable and roller bearing means interposed between said elements and constituting the sole connection between said elements for all fclosed positions of said switch, said roller bearing means being free to travel equally relative to both of said elements when said switch is moved out of closed position.

13. An electric switch comprising a pair of relatively movable switch elements having substantially parallel opposed faces and roller bearing means interposed between said faces and holding said faces apart and constituting `the sole electrical connection between said switch elements for all closed positions of said switch, said roller bearing means being free to roll equally on both of said opposed faces when said switch is opened.

14. An electric switch comprising a movable switch blade, a roller bearing upon which said blade rides for all closed positions of said switch and a supporting surface along which said bearing rolls when said blade is moved from its closed position.

15. An electric switch comprising fixed and movable contact members, roller bearing means interposed betwen said members and upon which said movable member rides when said switch is closed, said bearing means being free to roll along the surface of said fixed member, said movable member being poised upon said roller bearing when in normal closed position to facilitate opening of said lswitch from said closed position.

16. An electric switch comprising a pair of Contact members, movable relative to each other, roller bearing means interposed between said members and upon which said members are poised when said switch is in normal closed position to permit easy opening of said switch, said bearing means being free to roll along the surface of both of said members, one of said members having. a depression'therein to form a seat for said roller bearing means when said switch is closed to prevent accidental opening of said switch.

17. An electric switch comprising a pair of contact members having substantially parallel opposed faces movable relative to each other in a direction parallel to said faces and roller bearing means interposed between said faces and free to roll along both of said faces, said faces being poised upon said roller bearing means when said switch is in its normal closed position to provide electrical connection between said contact members and to facilitate opening of said switch.

18. An electric switch comprising a fixed contact member and spaced roller bearing means thereon, said bearing means being free to travel along said fixed contactl member, and a blade movable into position between said roller bearing means to form electrical connection through said roller bearing means with said fixed contact member, said blade being poised between said roller bearing means when said switch is in its normal closed position to facilitate movement of said blade out of said closed position.

19. An electric switch comprising a fixed contact member, a blade movable into and vout of electrical connection with said Contact member, said blade and contact member having substantially parallel contact faces and roller bearing means interposed between said faces and free to roll along both of said faces, said blade being poised upon said roller bearing means when in its normal closed position to permit easy movement of said blade out of said position.

In testimony whereof I have signed my name to this specification on this 21st day of May, A. D. 1925.

ARTHUR O. AUSTIN. 

